Part one draws a lot of biblical parallels. In addition to O the Scientist being God, Ahrima can be seen as a Composite Character between Lucifer (whose name means "light bringer" and who also became a Fallen Angel due to excess of pride) and Eve (who is tempted by a talking animal into committing the world's first sin). This would logically make Toba the Tura, who banishes Ahrima to "a fiery abyss", the Archangel Michael.
In one stage version, Pallis stabs the Doctor shortly after he enters. You can see it here.
Also, while a century is indeed a long passage of time, it is treated as multiple generations, given that Adakias’ surprise that Ahrima is his ancestor. A century isn’t all THAT long, it would have made more sense if it was maybe a couple of centuries.
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